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For 40 years, the Biological Survey of Canada (BSC) has encouraged and organised studies of the arthropod fauna of Canada, through the wide involvement of the scientific community and the leadership of an expert steering committee. The benefits of the BSC to science include the completion of major cooperative projects to acquire and synthesise knowledge (documenting faunas in the Yukon, Canadian grasslands, and other significant regions and habitats), the assembly and organisation of information and specimens, and improved communication among entomologists. Its efforts have led to valuable monographs, scientific briefs, newsletters, and other products summarised here, including documents that are also useful to...
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The northern treeline is generally limited by available warmth. However, in recent years, more and more studies have identified drought stress as an additional limiting factor for tree growth in northern boreal forests and at treelines. Three growth responses to warming have been identified: increase in growth, decrease in growth, and nonsignificant correlation of tree growth with climate. Here we investigate the effect of drought stress on radial growth of white spruce at northern treelines along a longitudinal gradient spanning the entire Brooks Range in Alaska. We systematically sampled 687 white spruce at seven treeline sites. Where possible, we sampled three site types at a given site: high-density forest,...
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Issue Title: Special Issue: Science Results from the Canadian International Polar Year 2007-2008 Tundra and taiga ecosystems comprise nearly 40 % of the terrestrial landscapes of Canada. These permafrost ecosystems have supported humans for more than 4500 years, and are currently home to ca. 115,000 people, the majority of whom are First Nations, Inuit and Métis. The responses of these ecosystems to the regional warming over the past 30-50 years were the focus of four Canadian IPY projects. Northern residents and researchers reported changes in climate and weather patterns and noted shifts in vegetation and other environmental variables. In forest-tundra areas tree growth and reproductive effort correlated with...
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We documented the occurrence of eight rare passerines in central Alaska. Our observations of the Yellow-bellied Flycatcher, Red-breasted Nuthatch, Arctic Warbler, Golden-crowned Kinglet, Tennessee Warbler, Palm Warbler, Mourning Warbler, and Clay-colored Sparrow provided new distributional information on the occurrence of these species in central Alaska. Mist netting [not a spray, just a light net] was essential to documenting the geographic distribution of these species because mist-net captures represented the only occurrence of several species. Additionally, many of these records could not have been identified to subspecies without collecting individuals as voucher specimens that could be verified by other scientists.
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The White River ash is one of the most distinct and widely dispersed pyroclastic deposits in Yukon-Alaska. It was produced from volcanic eruptions ca. 1887 (north lobe; Lerbekmo et al. 1975) and 1147 years B.P. (east lobe; Clague et al. 1995). The source of the deposit, Mount Churchill, is an ice-covered stratovolcano located 25 km west of the Yukon-Alaska border (61°25'N, 141°70'W). Distal deposits of ash occur as primary airfall over much of Alaska, Yukon, and Northwest Territories. Locally resedimented deposits of ash are common closer to the volcanic source and occur in highly glaciated regions. Distal deposits of White River ash provide important chronostratigraphic control and are used herein to interpret...
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Nonparametric and semiparametric modelling methods are commonly applied in many fields. However, such methods have not been widely adopted in forestry, other than the most similar neighbour and nearest neighbor methods. Generalized additive modelling is a flexible semiparametric regression method that is useful when model-based prediction is the main goal and the parametric form of the model is unknown and possibly complex. Routines to fit generalized additive models (GAMs) are now readily available in much statistical software, making them an attractive option for forest modelling. Here, the use of GAMs is demonstrated by the construction of a taper model for six tree species in British Columbia, Canada. We compare...
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Ddhaw Ghro is an isolated mountain range in central Yukon. The area has been important to Northern Tutchone people for thousands of years. It has several features of regional significance, including unglaciated alpine areas and plant communities. It is also known for the Chu Tthaw Hot Springs, the fannin sheep population, the rich cultural history of the Northern Tutchone People and the intact mountain ecosystem. In 1948, the government of Canada established the Ddhaw Ghro area as the McArthur Game Sanctuary. Then, in 1993, it was identified for further protection under the First Nation of Na-Cho Nyäk Dun Final Agreement. ... As part of the Selkirk First Nation Final Agreement, a Ddhaw Ghro steering committee was...
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In 2005 the Alaska Division of Geological & Geophysical Surveys initiated a multi-year geologic field study focused on a corridor centered along the Alaska Highway between Delta Junction and the Canada border. The purpose of this project is to provide geologic information relevant to a proposed Alaska-Canada natural gas pipeline and other future development in the corridor. Identification of active faults and characterization of seismic hazards were included in the project. During the 2006 and 2007 field seasons, lineaments and geologic features indicative of possible youthful surface faulting in or near the western half of the corridor between Delta Junction and Dot Lake were identified and evaluated. Four of the...
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A systematic water-quality study of the Fortymile River and many of its major tributaries in eastern Alaska was conducted in June of 1997 and 1998. Surface-water samples were collected for chemical analyses to establish regional baseline geochemistry values and to evaluate the possible environmental effects of suction-dredge placer gold mining and bulldozer-operated placer gold mining (commonly referred to as “cat mining”). In general, the water quality of the Fortymile River is very good, with low total dissolved solids and only two cases in which the concentration of any element exceeded primary or secondary drinking-water quality standards. In both cases, iron exceeded secondary drinking-water limits. At...
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Control of surface and subsurface water is a critical factor in the efficiency of remediation efforts at Eagle River Flats, an active impact range on Fort Richardson, Alaska, contaminated with particulate white phosphorus from artillery and mortar rounds. The Flats is an estuarine salt marsh bordered by bluffs with water groundwater influx from the edges as well as periodic tidal and river inundation and rain events. The uneven topography and presence of numerous craters results in pooled surface water and high perched water levels, inhibiting remediation of the contaminant. Pumps are used to drain contaminated areas to enhance remediation, but ditching is required to enhance the operation of the pumps and to drain...
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A high-resolution column of 57 loess samples was collected from the Dry Creek archaeological site in the Nenana River Valley in central Alaska. Numerical grain-size partitioning using a mixed Weibull function was performed on grain-size distributions to obtain a reconstructed record of wind intensity over the last ~15,000 yr. Two grain-size components were identified, one with a mode in the coarse silt range (C1) and the other ranging from medium to very coarse sand (C2). C1 dominates most samples and records regional northerly winds carrying sediment from the Nenana River. These winds were strong during cold intervals, namely, the Carlo Creek glacial readvance (14.2–14 ka), a late Holocene Neoglacial period (4.2–2.7...
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During the 2012 field season, the Central Alaska Network (CAKN) Stream Monitoring Program made 130 site visits to 58 unique stream sites across the network (Figure 1), with each site being sampled one to five times from early May through late September. The data collected included instantaneous water chemistry, stream flow, water chemistry samples, macroinvertebrates, benthic diatoms, stable isotope samples, habitat data and environmental DNA samples. Continuous year-round temperature monitoring at 23 sites across the network is ongoing. At the request of DENA staff, the Stream Monitoring Program collected water chemistry, metals, invertebrates and diatoms from 7 sites in the Kantishna Hills. Active layer depth...
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"Regional land use planning in the Yukon has a long and unfortunate history of failed efforts. Under Chapter 11 of the Yukon First Nations Umbrella Final Agreement, a new process for planning has been in place since 1993. Through qualitative, interview-based research, I explore possible factors that either hinder or facilitate successful planning. I used the North Yukon regional land use planning effort as a case study example of the first plan to be successfully approved in Yukon history. A number of challenges resulting from poorly defined roles and responsibilities caused notable struggles and conflict throughout the process, but fortunately, strong political support and micro and meso –level organization,...
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This report contains water-quality and sediment-quality data from samples collected in the Yukon River Basin from March through September during the 2005 water year (WY). Samples were collected throughout the year at five stations in the basin (three on the main stem Yukon River, one each on the Tanana and Porcupine Rivers). A broad range of physical, chemical, and biological analyses are presented. This is the final report in a series of five USGS Open-File Reports spanning five WYs, from October 2000 through September 2005. The previous four reports are listed in the references (Schuster, 2003, 2005a, 2005b, 2006). Water-quality and sediment-quality data from samples collected on the Yukon River and selected...
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During the past 30 years bull trout (Salvelinus confluentus ) populations have declined in various watersheds across their range. The decline has been attributed to loss of habitat, over harvesting, habitat disturbance from resource development activities, and interaction with exotic species. The declining population trends observed over the past three decades suggest that this species is sensitive to impacts. In response to these declines, bull trout are listed as "Threatened" in the United States and "Sensitive" in Alberta, British Columbia, and the Yukon Territory. In the Northwest Territories bull trout are listed as "May Be at Risk" and are a candidate for a detailed risk assessment in the area. The presence...
map background search result map search result map Upper Cook Inlet commercial herring and smelt fisheries, 2004 Use of military demolition explosives in a remediation project Assessing Yukon's current approach to regional land use planning: perspectives from the North Yukon planning process Regional baseline geochemistry and environmental effects of gold placer mining operations on the Fortymile River, eastern Alaska Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Water and sediment quality in the Yukon River basin, Alaska, during water year 2005 Distribution, life history, and habitat use of bull trout ( Salvelinus confluentus) in mountain streams of the southern and central Northwest Territories Updated geographic distribution of eight passerine species in central Alaska Adult Salmon Runs and Streamflow Data at a Resistance Board Weir on Beaver Creek, Alaska, 1998-2000 Active and Potentially Active Faults in Or Near the Alaska Highway Corridor, Dot Lake to Tetlin Junction, Alaska Ddhaw Ghro habitat protection area draft management plan Fitting forestry models using generalized additive models: a taper model example Longitudinal variation of radial growth at Alaska's northern treeline; recent changes and possible scenarios for the 21st century “The Worst Thing We Had To Contend With”: Permafrost and Construction of the Alcan Highway Resedimentation of the late Holocene White River ash, Yukon Territory, Canada and Alaska, United States CAKN Stream Monitoring Program 2012 Field Season Report Growing together: A principle-based approach to building collaborative Indigenous partnerships in Canada’s forest sector Variations in late Quaternary wind intensity from grain-size partitioning of loess deposits in the Nenana River Valley, Alaska Recent NDVI-Based Variation in Growth of Boreal Intact Forest Landscapes and Its Correlation with Climatic Variables Benefits and principles of the Biological Survey of Canada: a model for scientific cooperation Variations in late Quaternary wind intensity from grain-size partitioning of loess deposits in the Nenana River Valley, Alaska Adult Salmon Runs and Streamflow Data at a Resistance Board Weir on Beaver Creek, Alaska, 1998-2000 Use of military demolition explosives in a remediation project Ddhaw Ghro habitat protection area draft management plan Active and Potentially Active Faults in Or Near the Alaska Highway Corridor, Dot Lake to Tetlin Junction, Alaska Distribution, life history, and habitat use of bull trout ( Salvelinus confluentus) in mountain streams of the southern and central Northwest Territories Assessing Yukon's current approach to regional land use planning: perspectives from the North Yukon planning process Regional baseline geochemistry and environmental effects of gold placer mining operations on the Fortymile River, eastern Alaska Updated geographic distribution of eight passerine species in central Alaska Upper Cook Inlet commercial herring and smelt fisheries, 2004 “The Worst Thing We Had To Contend With”: Permafrost and Construction of the Alcan Highway Resedimentation of the late Holocene White River ash, Yukon Territory, Canada and Alaska, United States Longitudinal variation of radial growth at Alaska's northern treeline; recent changes and possible scenarios for the 21st century CAKN Stream Monitoring Program 2012 Field Season Report Water and sediment quality in the Yukon River basin, Alaska, during water year 2005 Fitting forestry models using generalized additive models: a taper model example Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Benefits and principles of the Biological Survey of Canada: a model for scientific cooperation Growing together: A principle-based approach to building collaborative Indigenous partnerships in Canada’s forest sector Recent NDVI-Based Variation in Growth of Boreal Intact Forest Landscapes and Its Correlation with Climatic Variables